Responses to toxins
Any substance or condition that is
harmful to the body can be considered a
toxin. The response of the body to toxins depends on both the susceptibility of the person and the nature of the toxin. Responses to
toxins vary widely from person to person. The nature of toxins also varies widely.
Susceptibility to toxins
People are not equally susceptible to the adverse effects of toxins. A person's susceptibility and response to toxins varies with age,
gender, health status, genetic factors, enzyme metabolism, nutritional status, and
lifestyle factors. These factors can cause a
wide variation in responses to toxins.
- AGE AND HEALTH STATUS
- Although infants have detoxification enzymes at birth, their detoxification rate is
slower than that of adults, causing them to
be easily affected by toxins. Children and
elderly people are more susceptible to toxins than healthy adults are.
People who have lowered immune defenses or impaired body defense mechanisms (such as the skin, the lungs, and the
gastrointestinal tract) are particularly affected by toxins. Because the majority of
detoxification takes place in the liver, people
with liver disease will be easily affected by toxins.
- GENDER
- Females are more sensitive to toxins than
are males. They are generally smaller than
men, and their lower weight causes them to
become ill from chemicals more quickly.
Women have more adipose (fatty) tissue and
thus more fat cells in which fat-soluble toxins are deposited.
Women have lower levels of the enzyme
alcohol dehydrogenase, and are less able to
detoxify alcohol. Women have higher levels
of estrogen and progesterone, which causes
them to sensitize more easily, as some detoxification enzymes are particularly sensitive to hormones. Hormonal changes during
pregnancy also affect detoxification enzyme
activity, increasing the ability to eliminate some drugs.
- GENETIC FACTORS
- Genetically determined differences in susceptibility to toxins is called ecogenetics. Genetics determine which enzymes are available for the body's detoxification processes,
and some people do not have enough
specific detoxification enzymes.
Geneticists theorize that as people are
exposed to more chemicals, more individuals with chemical susceptibility will be identified. More abnormal enzymes will be
demonstrated. The current observed genetic
variations probably represent only a small
fraction of the diversity that will be identified.
- GENETIC ENZYMATIC DEFECTS
- One or more of about 50 inherited enzymatic defects can determine a person's
susceptibility to chemicals. For example, the
enzyme alpha-I-antitrypsin continuously
protects the lungs from the proteolytic enzymes released from white blood cells. People with an alpha-I-antitrypsin deficiency
may be more sensitive to and suffer more adverse effects from air pollution than other
people. People with a homozygous deficiency (a defect in two genes) are at increased risk to develop emphysema.
Enzymatic defects are rare and most
have been identified from studying the metabolism of pharmaceutical drugs; they have
not been studied in relation to environmental pollutants. The metabolism of some drugs has been found to be controlled by a
single gene. Further investigation is expected to show that one gene can control the
metabolism of many drugs.
- ENZYME METABOLISM
- The efficiency of detoxification enzymes directly affects the rate of detoxification. One
of the enzymes that metabolizes drugs and
chemicals is debrisoquine hydroxylase. It is
controlled by a single gene, which has different forms (polymorphism). Individuals with
slow rates of debrisoquine hydroxylation
(poor metabolizers) are found more frequently in European populations than in Asian populations.
Parkinson's disease and lung cancer in
smokers have been associated with the slow
metabolism of chemicals by this enzyme. In
several epidemiological studies, Parkinson's
disease has been associated with pesticide
use. Patients who cannot metabolize and rid
their bodies of pesticides may be more susceptible to Parkinson's disease.
Another detoxification enzyme metabolizes S-carboxymethyl cysteine. Many people
with food sensitivities are poor metabolizers of this chemical, but vitamin C supplementation has sometimes been found to increase the activity of this enzyme. This may partially explain why large doses of vitamin C
are helpful for some allergy patients.
The slow metabolic action of another
group of enzymes has caused peripheral
neuritis (inflamed nerves in hands and feet)
and increased risk of bladder cancer in some
people. Many of these enzymes are part of
the cytochrome P-450 family, which constitute a major detoxification system.
- NUTRITIONAL STATUS
- Nutrient levels determine which vitamins, minerals, amino acids, and fatty acids are
available to the body. Many enzymes require
a particular vitamin and/or mineral in order
to function. If the nutrients are not present,
the enzyme becomes paralyzed or inactive,
and detoxification cannot take place, causing
increased susceptibility to new toxins. Diet
is very important for replenishing the needed nutrients.
- LIFESTYLE FACTORS
- Susceptibility to toxins also depends on the
total chemical burden of the body - the
quantity of chemicals competing for detoxification. Lifestyle directly determines the total burden. People who eat a nutrient-deficient diet and food contaminated with
additives, hormones, and preservatives will
add to their toxic load. Drugs, including prescription drugs, smoking, and alcohol consumption also contribute to toxic burdens.
Personal care, cleaning, and laundry products are toxic exposures for many people.
Lack of exercise and a sedentary lifestyle further contribute to the problem, as exercise is
necessary for the elimination of toxins.
People who are exposed to a myriad of
toxins and who do not take steps to detoxify
their bodies will become overloaded. Chemicals and toxins are stored in the fat, brain,
and other lipid tissues, such as cell membranes. New chemicals entering the body
cannot be metabolized because of the existing chemical overload. The backlogged
chemicals can damage the detoxification
system as well as the endocrine, nervous, and immune systems.
Nature of Toxins
Responses to toxins also vary with the nature
of the toxin. Many toxins, particularly external toxins, are chemicals. There is more documented information regarding the effects
of chemicals that are foreign to the body
(xenobiotics) than for other toxins. The Environmental Protection Agency (EPA) estimates that approximately 500,000 chemicals are in use today, and each year more
than 5,000 new chemicals are added. Our
bodies are exposed to many of these chemicals daily.
The response of the body to chemicals
can differ according to the structure of the
chemical. Some responses to toxins are immunological in nature, while others are not.
For example, many people develop asthma
in response to plicatic acid found in cedar.
This asthma is caused by an antigen-antibody response initiated by the immune system. The plicatic acid acts as an antigen, and
the body produces antibodies in response.
Other people experience an asthma attack
when exposed to formaldehyde, but do not
have an antigen-antibody response. Their response is caused by a different mechanism.
Many chemicals that the body absorbs
tend to remain in the tissues for long periods
of time. Most of these chemicals are lipophilic, which means they dissolve readily
in fat, one of the main components of cell
membranes. Lipophilic, or lipid-soluble,
chemicals are complex and difficult for the
body to break down and excrete, whereas water-soluble chemicals can be excreted unchanged or after undergoing simple metabolic changes. If a chemical is lipid-soluble
and nonpolar (uncharged), it has to undergo two chemical steps or phases to become a
polar (charged), water-soluble chemical.
Specific enzymes are required for these conversions.
The exposure dose of the chemical and
the length of the exposure can also affect the
response of the body to a particular toxin.
Large, overwhelming doses can be more
toxic immediately than smaller doses over a
long period of time. The efficiency of the
detoxification mechanisms, individual tissue sensitivities to the chemical, and efficiency of the excretion systems of the body
also affect the toxicity of a chemical.
The body processes or detoxifies substances produced by the body, such as hormones, vitamins, cholesterol, and fatty
acids, in the same way that it detoxifies xenobiotics. Even though they are endproducts of
metabolism and natural substances, they
would become toxic (internal toxins) if allowed to build up. The same detoxification
mechanisms that detoxify xenobiotics detoxify these internal toxins.
There are many toxins that are not chemicals, including weather, altitude, noise, radiation, geopathic stress, electromagnetic fields, emotional trauma, loss of spirituality and faith, and cumulative life experiences. These non-chemical toxins are removed from the body by various mechanisms, depending on the toxin. Some are removed by mechanisms within the body; others are cleansed by external processes and techniques. For example, techniques needed to
detoxify mind and spirit toxins are very
different from those necessary to remove chemical toxins.
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